Microbiology and Immunology

Chain, Ernst Boris WORLD OF MICROBIOLOGY AND IMMUNOLOGY

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to 20 years later. This long-lasting form of Chagas disease

reduces the life span by almost a decade.

Chagas disease may be asymptomatic (without symp-

toms)—or can produce a variety of symptoms. The form of the

disease that strikes soon after infection with Trypanosoma

cruzitends to persist only for a few months before disappear-

ing. Usually, no treatment is necessary for relief from the

infection. Symptoms of this type of so-called acute infection

include swelling at the site of the bug bite, tiredness, fever,

enlarged spleen or liver, diarrhea, and vomiting. Infants can

experience a swelling of the brain that can be fatal.

The chronic form of Chagas disease can produce more

severe symptoms, including an enlarged heart, irregularities in

heart function, and the enlargement and malfunction of the

digestive tract. These symptoms are of particular concern in

those people whose immune systemis not functioning properly.

Currently, there is no vaccineor other preventative

treatment for Chagas disease. Avoidance of habitats where the

Reduviid bug lives is the most prudent precaution.

Unfortunately, given the economic circumstances of those

most at risk, this option is not easily attainable. Trypanosoma

cruzican also be transmitted in the blood. Therefore, screen-

ing of blood and blood products for the presence of the proto-

zoan is wise. Once again, however, the poverty that often

plays a role in the spread of Chagas disease may also be

reflected in less than adequate medical practices, including

blood screening.

See alsoParasites; Zoonoses

CChain, Ernst BorisHAIN, ERNSTBORIS (1906-1979)

German–born English biochemist

Ernst Chain was instrumental in the creation of penicillin, the

first antibiotic drug. Although the Scottish bacteriologist

Alexander Flemingdiscovered the penicillium notatummold

in 1928, it was Chain who, together with Howard Florey, iso-

lated the breakthrough substance that has saved countless

victims of infections. For their work, Chain, Florey, and

Fleming were awarded the Nobel Prize in physiology or

medicine in 1945.

Chain was born in Berlin to Michael Chain and

Margarete Eisner Chain. His father was a Russian immigrant

who became a chemical engineer and built a successful chem-

ical plant. The death of Michael Chain in 1919, coupled with

the collapse of the post–World War I German economy,

depleted the family’s income so much that Margarete Chain

had to open up her home as a guesthouse.

One of Chain’s primary interests during his youth was

music, and for a while it seemed that he would embark on a

career as a concert pianist. He gave a number of recitals and

for a while served as music critic for a Berlin newspaper. A

cousin, whose brother–in–law had been a failed conductor,

gradually convinced Chain that a career in science would be

more rewarding than one in music. Although he took lessons

in conducting, Chain graduated from Friedrich–Wilhelm

University in 1930 with a degree in chemistry and physiology.

Chain began work at the Charite Hospital in Berlin

while also conducting research at the Kaiser Wilhelm Institute

for Physical Chemistry and Electrochemistry. But the increas-

ing pressures of life in Germany, including the growing

strength of the Nazi party, convinced Chain that, as a Jew, he

could not expect a notable professional future in Germany.

Therefore, when Hitler came to power in January 1933, Chain

decided to leave. Like many others, he mistakenly believed

the Nazis would soon be ousted. His mother and sister chose

not to leave, and both died in concentration camps.

Chain arrived in England in April 1933, and soon

acquired a position at University College Hospital Medical

School. He stayed there briefly and then went to Cambridge to

work under the biochemist Frederick Gowland Hopkins.

Chain spent much of his time at Cambridge conducting

research on enzymes. In 1935, Howard Florey became head of

the Sir William Dunn School of Pathology at Oxford. Florey,

an Australian–born pathologist, wanted a top–notch bio-

chemist to help him with his research, and asked Hopkins for

advice. Without hesitation, Hopkins suggested Chain.

Florey was actively engaged in research on the bacteri-

olytic substance lysozyme, which had been identified by

Fleming in his quest to eradicate infection. Chain came across

Fleming’s reports on the penicillin mold and was immediately

intrigued. He and Florey both saw great potential in the further

investigation of penicillin. With the help of a Rockefeller

Foundation grant, the two scientists assembled a research team

and set to work on isolating the active ingredient in

Penicillium notatum.

Fleming, who had been unable to identify the antibac-

terial agent in the mold, had used the mold broth itself in his

experiments to kill infections. Assisted in their research by fel-

low scientist Norman Heatley, Chain and Florey began their

work by growing large quantities of the mold in the Oxford

laboratory. Once there were adequate supplies of the mold,

Chain began the tedious process of isolating the “miracle”

substance. Succeeding after several months in isolating small

amounts of a powder that he obtained by freeze–drying the

mold broth, Chain was ready for the first practical test. His

experiments with laboratory mice were successful, and it was

decided that more of the substance should be produced to try

on humans. To do this, the scientists needed to ferment mas-

sive quantities of mold broth; it took 125 gallons of the broth

to make enough penicillin powder for one tablet. By 1941,

Chain and his colleagues had finally gathered enough peni-

cillin to conduct experiments with patients. The first two of

eight patients died from complications unrelated to their infec-

tions, but the remaining six, who had been on the verge of

death, were completely cured.

One potential use for penicillin was the treatment of

wounded soldiers, an increasingly significant issue during the

Second World War. For penicillin to be widely effective, how-

ever, the researchers needed to devise a way to mass–produce

the substance. Florey and Heatley went to the United States in

1941 to enlist the aid of the government and of pharmaceutical

houses. New ways were found to yield more and stronger peni-

cillin from mold broth, and by 1943, the drug went into regu-

lar medical use for Allied troops. After the war, penicillin was

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